V0.0.8[*] & V1.1.4[+]

*Test new base class of graphics item - CGraphicsWidget
*CDayWidget inherit from CGraphicsWidget
*Remove CDayItem
V0.0.8[*] & V1.1.5[+]

+Add CDayWidget inherited from CGraphicsWidget
+Add CMonthWidget inherited from CGraphicsWidget
+Add CYearWidget inherited from CGraphicsWidget
+Add CPlanWidget inherited from CGraphicsWidget
+Remove CDayItem, CMonthItem, CYearItem
+Add time + task = plan framework for task management